Tracking device and system for simulated combat and related civilian applications

ABSTRACT

A tracking device, a related combat simulator, and methods for their use. The tracking device comprises a SPS receiver, a communications interface for reversibly mounting therein a communications card, a combat simulation device interface, and a control unit for receiving location data from the SPS receiver, for transmitting the location data via the communications interface, and for exchanging combat simulation data between the combat simulation device interface and the communications interface. The combat simulator includes a control center for controlling several tracking devices. For civilian applications, the combat simulation device interface is replaced with an alarm button.

FIELD AND BACKGROUND OF THE INVENTION

[0001] The present invention relates to tracking devices and systems and, more particularly, to a tracking device, and a system based on these devices, for monitoring the movements of subjects. In military applications of the present invention, the subjects are participants in simulated combat.

[0002] Modern armies use laser-based combat simulation devices for training purposes, to preclude the expense and danger of using live ammunition. For example, such devices are used in the U.S. Army's MILES (Multiple Integrated Laser Engagement System) 2000 and by the U.S. Army's MILES 3 system. Each participant in a training exercise that uses the MILES 2000 system is provided with a combat simulation device that includes a simulated weapon and a target sensor. The simulated weapon includes an infrared laser that is fired by the participant, acting as an aggressor, at other participants. The target sensor is an infrared sensor that registers hits by laser beams of other participants. The lasers and the target sensors are tuned so that the signals provided by the target sensors are representative of the damage that real weapons would inflict on real targets. Whenever a laser is fired, and whenever a target sensor is hit, corresponding signals are transmitted to a control center to provide the control center with data relating to the simulated combat effectiveness of the participants. Note that the participants may be individual soldiers or combat vehicles or a mixture of both. In addition, whenever a target sensor is hit, that target sensor activates an effects simulation system on the target that produces a special effect indicative of the hit. For example, an effects simulation system on a tank may set off a pyrotechnic device.

[0003] One limitation of prior art systems such as MILES 2000 is that the transceivers used by the participants and by the control center are military transceivers that are specific to their respective armies. This limits the interoperability of these systems for joint training exercises of allied armies.

[0004] There is thus a widely recognized need for, and it would be highly advantageous to have, a combat simulation system that allows interoperability among several allied armies. As will be seen below, such a system, suitably modified, would also have important civilian applications.

SUMMARY OF THE INVENTION

[0005] According to the present invention there is provided a tracking device, including: (a) a SPS receiver; (b) a communications interface for reversibly mounting therein a communications card; (c) a combat simulation device interface; and (d) a control unit for receiving location data from the SPS receiver, for transmitting the location data via the communications interface, and for exchanging combat simulation data between the combat simulation device interface and the communications interface.

[0006] According to the present invention there is provided a combat simulation system including: (a) a control center including: (i) a control center communications interface for reversibly mounting therein a control center communications card that operates according to a communications protocol, and (ii) a control center transceiver, operationally connected to the control center communications interface; and (b) a plurality of tracking devices, each tracking device including: (i) a combat simulation device interface, (ii) a SPS receiver, (iii) a tracking device communications interface for reversibly mounting therein a tracking device communications card that operates according to the communications protocol, (iv) a tracking device transceiver, operationally connected to the tracking device communications interface, for transmitting transmitted signals to the control center and receiving received signals from the control center via the control center transceiver, and (v) a control unit for: (A) receiving location data from the SPS receiver, (B) transmitting the location data to the control center via the tracking device transceiver and the control center transceiver, and (C) exchanging combat simulation data between the combat simulation device interface and the control center, via the tracking device transceiver and the control center transceiver, the data being transmitted and received by the transceivers as the signals.

[0007] According to the present invention there is provided a tracking device, including: (a)a SPS receiver; (b)a communications interface for reversibly mounting therein a communication card; (c) a personal sensor; and (d) a control unit for receiving location data from the SPS unit, for receiving personal status data from the personal sensor, and for transmitting the data via the communications interface.

[0008] According to the present invention there is provided a tracking device, including: (a) a SPS receiver; (b) a communications interface for reversibly mounting therein a communication card; (c) an alarm button for activating a transmission of an alarm signal via the communications interface; and (d) a control unit for receiving location data from the SPS unit, for transmitting the data via the communications interface, and for including at least a portion of the location data in the alarm signal.

[0009] According to the present invention there is provided a personal tracking system including: (a) a control center including: (i) a control center communications interface for reversibly mounting therein a control center communications card that operates according to a communications protocol, and (ii) a receiver, operationally connected to the control center communications interface; and (b) a plurality of tracking devices, each tracking device including: (i) a SPS receiver, (ii) a tracking device communications interface for reversibly mounting therein a tracking device communications card that operates according to the communications protocol, (iii) a personal sensor; (iv) a transmitter, operationally connected to the tracking device communications interface, for transmitting signals to the control center via the receiver, and (v) a control unit for: (A) receiving location data from the SPS receiver, (B) receiving personal status data from the personal sensor, and (C) transmitting the data to the control center via the transmitter and the receiver, the data being transmitted by the transmitter and received by the receiver as the signals.

[0010] According to the present invention there is provided a personal tracking system including: (a) a control center including: (i) a control center communications interface for reversibly mounting therein a control center communications card that operates according to a communications protocol, and (ii) a receiver, operationally connected to the control center communications interface; and (b) a plurality of tracking devices, each tracking device including: (i) a SPS receiver, (ii) a tracking device communications interface for reversibly mounting therein a tracking device communications card that operates according to the communications protocol, (iii) a transmitter, operationally connected to the tracking device communications interface, for transmitting signals to the control center via the receiver, one of the signals being an alarm signal, (iv) an alarm button for activating a transmission of the alarm signal, and (v) a control unit for receiving location data from the SPS receiver, for transmitting the data to the control center via the transmitter and the receiver, the data being transmitted by the transmitter and received by the receiver as the signals, and for including at least a portion of the location data in the alarm signal.

[0011] According to the present invention there is provided a method of simulating combat between an aggressor participant and a defender participant, including the steps of: (a) providing each participant with a tracking device including: (i) a SPS receiver; and (ii) a communications interface for reversibly mounting therein a communications card, both the communications cards operating according to a common communications protocol; (b) providing each participant with a combat simulation device operationally coupled to the tracking device of the each participant; (c) providing a control center for coordinating the simulated combat; (d) simulating an attack by the aggressor participant against the defender participant, using respective the combat simulation devices, the simulating including the steps of: (i) for each participant, determining a location of the each participant, using the respective SPS receiver, and (ii) for each participant, transmitting data related to the attack to the control center via the respective communications interface, the data of each participant including the respective location.

[0012] According to the present invention there is provided a method of monitoring a location and a condition of a subject, including the steps of: (a) providing the subject with a tracking device including: (i) a SPS receiver, (ii) a communications interface for reversibly mounting therein a communications card, and (iii) a condition sensor for sensing a value of a physiological parameter of the subject; (b) providing a control center; (c) periodically sensing the value, by the tracking device, using the condition sensor; and (d) if the value is outside a predetermined range: (i) determining the location of the subject, by the tracking device, using the SPS receiver, and (ii) transmitting, to the control center, by the tracking device, via the communications interface, an indication of the location and of the value.

[0013] According to the present invention there is provided a method of monitoring a location of a subject, including the steps of: (a) providing the subject with a tracking device including: (i) a SPS receiver, and (ii) a communications interface for reversibly mounting therein a communications card; (b) providing a control center; and (c) activating the tracking device, by the subject, to: (i) determine the location of the subject, using the SPS receiver, and (ii) transmit the location to the control center, via the communications interface.

[0014] The tracking devices and the control center of the present invention provides the desired interoperability by relying on civilian communications networks for communicating with each other. A military tracking device of the present invention includes an interface to a combat simulation device, a Satellite Positioning System (SPS) receiver for determining the participants location on demand, and a communications unit. The communications unit includes a transceiver, a communications card that enables the communications unit to operate according to a local civilian communications protocol, and an interface into which the communications card is reversibly inserted. Typically, the interface to the communications card is either a PCMCIA interface or a serial (e.g., RS232) interface. Thus, the present invention is modular: the communications interface allows the use of different communications cards in different geographical locations. For example, a preferred embodiment of the tracking device of the present invention includes communications cards that operate according to the CDMA IS-95 protocol used for voice and data cellular telephony in North America, the GSM protocol used for cellular telephony in Europe and Asia (most preferably using the General Packet Radio Service (GPRS)), the CDPD protocol used for mobile radio communications and cellular telephony in North America and Israel, and the TETRA protocol used for mobile radio communications in Europe. The control center is equipped similarly with a transceiver, a communications card that enables the control center to communicate with the tracking devices according to the local civilian communications protocol via the corresponding local civilian communications network, and a communications interface into which the control center's communications card is reversibly inserted. Each tracking device also includes a control unit for receiving data from the SPS receiver and for exchanging data with the communications interface.

[0015] When a combat simulation system of the present invention is taken from one region that uses one civilian communications protocol, to another region that uses a different civilian communications protocol, for example from North America to Europe, all that is needed to modify the system is to exchange the communications cards of the old region for the communications cards of the new region.

[0016] The preferred SPS receiver of the present invention is a GPS receiver, although the scope of the present invention includes other SPS receivers, for example GLONASS receivers.

[0017] When a participant acting as an aggressor fires its simulated weapon, or when the target sensor of a participant senses a hit by an aggressor's laser beam, signals indicative of these events are transmitted by the transceivers of the respective tracking devices to the control center, via the local civilian communications network and the control center transceiver. These signals include geographical coordinates and time stamps obtained from the SPS receivers of the respective tracking devices. The control center transmits control signals to the participants as needed, using its own transceiver, also via the local civilian communications network and the participants' transceivers. Examples of these control signals include an indication to a participant that it has fired its laser as often as allowed and so is “out of ammunition”, and an indication to a participant that it has suffered severe enough hits to put it out of action. “Exchange” of such signals between a tracking device and the control center is understood herein to refer both to the transmission of signals from the tracking device to the control center, with receipt of the signals by the control center, and the transmission of signals from the control center to the tracking device, with receipt of the signals by the tracking device. Similarly, the “exchange” of data between the control unit of a tracking device and the communications interface of the tracking device is understood herein to refer both to the formatting of data by the control unit for transmission to the communication interface and the transmission of these data to the communication interface for transmission by the transceiver as transmitted signals according to the relevant communications protocol, and to the reception of data by the control unit from the communications interface as the communications interface receives these data consequent to the receipt of corresponding signals by the transceiver.

[0018] Preferably, the formatting of data for transmission by the control unit includes compression of the data. Correspondingly, the receipt of data by the control unit from the communications interface includes decompression of the received data.

[0019] Periodically, each tracking unit determines its location, using the SPS receiver, independent of any activity of the combat simulation device, and transmits that location to the control center. This allows the control center to tell when a participant enters an area that is off-limits (illegal) and to transmit a corresponding signal to the trespassing participant.

[0020] Preferably, a tracking device of the present invention for personal use includes a personal sensor, such as a pulse rate sensor or a thermometer, for monitoring a physiological status of the participant. When data received by the control unit from the personal sensor indicate that the value of the corresponding physiological parameter of the participant is outside the normal range of that parameter, the control unit transmits a corresponding warning signal to the control center. This warning signal includes the location of the participant, as determined using the SPS receiver. Similarly, a preferred embodiment of the tracking device of the present invention includes an alarm button that allows the participant itself to activate the transmission of a similar alarm when the participant perceives itself to be in danger.

[0021] Preferably, the control unit of a tracking device of the present invention includes a memory for storing copies of the simulated combat event data that are transmitted to the control center and that are received from the control center.

[0022] A civilian tracking device of the present invention lacks an interface to a combat simulation device. In all other respects, the civilian tracking device of the present invention is identical to the military tracking device of the present invention, and the civilian control center of the present invention is identical to the military control center of the present invention. Those skilled in the art will be able to envision many civilian applications of the present invention. These include:

[0023] locating lost children in an amusement park, with the control center being located at the amusement park office. Each visitor to the amusement park is provided with a vest, belt or holster that contains a civilian tracking device of the present invention.

[0024] monitoring the condition of livestock on the open range, with the control center being located at ranch headquarters. Each animal is provided with a harness that contains a civilian tracking device of the present invention.

[0025] Because the person or animal who is provided with the civilian tracking device of the present invention is not competing with another person or animal, this person or animal is referred to herein as a “subject” rather than a “participant”.

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein:

[0027]FIG. 1 is a schematic block diagram of a tracking device of the present invention;

[0028]FIG. 2 is a schematic illustration of a combat simulation system of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] The present invention is of a tracking device, and an associated tracking system, which can be used to track the locations and conditions of subjects such as people, vehicles and livestock. Specifically, in a military application thereof, the present invention can be used to enhance simulated combat, and in a civilian application thereof, the present invention can be used to locate missing persons and animals and to identify and locate persons and animals in distress.

[0030] The principles and operation of a tracking device and system according to the present invention may be better understood with reference to the drawings and the accompanying description. More specifically, the present invention is described below with reference to its primary military application, simulated combat. It will be clear to those skilled in the art how to apply the principles of the present invention to its civilian applications.

[0031] Referring now to the drawings, FIG. 1 is a schematic block diagram of a tracking device 10 of the present invention. The heart of tracking device 10 is a control unit 28. Operationally connected to control unit 28 are a SPS receiver 12 (specifically, a GPS receiver), an interface 14 to a combat simulation device 16 (specifically a MILES 2000), an interface 18 to a communications card 20, a transceiver 22, a physiological sensor 30, a speaker 31, an alarm button 32 and a power supply 36. Interface 18 is such that communications card 20 may be removed therefrom and replaced with a different communications card 20. Usually, tracking device 10 comes with several communications cards 20, each one specific to a different communications protocol. Four such communications cards 20 are shown in FIG. 1: a communications card 20 that operates according to the CDPD protocol, a communications card 20 that operates according to the CDMA I-95 protocol, a communications card 20 that operates according to the GSM protocol and a communications card 20 that operates according to the TETRA protocol. Communications card 20 that operates according to the GSM protocol is shown mounted in interface 18. Suitable commercially available communications cards 20 include the AirCard 210 series, available from Sierra Wireless Inc. If Vancouver, British Columbia, Canada. Most preferably, interface 14, like interface 18, is such that combat simulation device 16 may be removed therefrom and replaced with a different combat simulation device.

[0032] Most preferably, GPS receiver 12 is a differential GPS receiver.

[0033] Transceiver 22 includes both transmit functionality 24 and receive functionality 26. Transceiver 22 operates, under the control of control unit 28 and communications card 20, to transmit data provided by control unit 28 as signals according to the specific communications protocol of communications card 20, and to receive signals, according to the specific communications protocol of, that are interpreted as input data for control unit 28.

[0034] Control unit 28 exchanges combat simulation data with combat simulation device 16 via interface 14. Control unit 28 also receives input data from GPS receiver 12, sensor 30 and alarm button 32. The input data from GPS receiver 12 are data indicating the location of tracking device 10. Because the simultaneous equations solved by GPS receiver 12 include, as one of the unknowns thereof, the bias of the internal clock of GPS receiver 12 relative to the time kept by the GPS system, the input data from GPS receiver 12 also include a timestamp indicating the time when tracking device 10 was determined to be at that location. The input data from sensor 30 are values of a physiological parameter of a user of tracking device 10. Preferred examples of sensor 30 include a pulse rate sensor and a thermometer. The input datum from alarm button 32 is an activation signal, as described below.

[0035] Control unit 28 also includes a memory 34 for recording simulated combat events, as illustrated below.

[0036] Control unit 28 and transceiver 22 are powered by a power module 36. Power module 36 includes two rechargeable batteries 38 and 39, and an interface 40 to a 12 volt vehicular DC power supply. Primary battery 38 is replaceable ,and powers tracking device 10 during normal use. Secondary battery 39 is installed permanently in power module 36 and is kept charged by primary battery 38. The main function of secondary battery 39 is to preserve the data stored in memory 34 while tracking device 10 is turned off.

[0037] Tracking device 10, as illustrated in FIG. 1, can be used by a participant who is either a person or a vehicle. When mounted on a vehicle, tracking device 10 obtains power via interface 40. When carried by a person, tracking device 10 obtains power from battery 38. Physiological sensor 30 is specific to a participant who is a person; but it will be appreciated that a sensor appropriate to a vehicle could be substituted for physiological sensor 30.

[0038]FIG. 2 illustrates, schematically, a combat simulation system of the present invention. The combat simulation system includes, in addition to a plurality of tracking devices 10, a control center 50 that exchanges signals with tracking devices 10. Control center 50 includes an interface 52 to a communications card. Like interface 18, interface 52 is such that a communications card may be removed therefrom and replaced with a different communications card. Indeed, the communications cards that are mounted reversibly in interface 52 is identical to the communications cards that are mounted reversibly in interfaces 18 of tracking devices 10. Therefore, the communications card in FIG. 2 is designated by the same reference numeral 20 as is used to designate the communications card of tracking device 10 in FIG. 1. Operationally connected to interface 52 is a transceiver 54 that includes both transmit functionality 56 and receive functionality 58. Note that only the components of control center 50 that are germane to an explanation of the present invention are depicted in FIG. 2. For example, control center 50 necessarily includes a control unit and a power supply, neither of which are shown in FIG. 2.

[0039] Most preferably, if communication between control center 50 and tracking devices 10 is via a civilian cellular telephony network, control center 50 also includes a landline connecting interface 52 to the civilian network. This reduces the wireless traffic burden on the civilian network consequent to the operation of the present invention.

[0040] Also shown in FIG. 2 are two participants 42 in simulated combat. Each participant 42 is equipped with a respective tracking device 10. Some components of tracking devices 10 are illustrated separately: simulated weapon 44, a part of combat simulation device 16 of tracking device 10 a; target sensor 46, a part of combat simulation device 16 of tracking device 10 b; and physiological sensor 30 of tracking device 10 b. Sensor 30 is a pulse rate sensor, mounted in close proximity to the left femoral pulse of participant 42 b. Tracking devices 10 a and 10 b communicate with control center 50 via base transceiver stations (BTSs) 60 of a cellular telephony network that operates according to the GSM communications protocol. Consequently, communications cards 20 of tracking devices 10 a and 10 b and of control center 50 all operate according to the GSM communications protocol.

[0041] A secondary function of secondary battery 39 of tracking device 10 is to power the transmission of a “shutoff” message from tracking device 10 to control center 50 when tracking device 10 is turned off.

[0042] Also shown in FIG. 2 are two satellites 62 of the GPS constellation. GPS receivers 12 of tracking devices 10 determine their locations based on signals received from satellites 62. If GPS receivers 12 are differential receivers, control center 50 sends differential correction data to tracking devices 10, using a standard protocol such as the NEMA protocol. GPS receivers 12 use this differential correction data, as is well-known in the art, to account for the ≈50 meter error that is included by the U.S. Department of Defense in the civilian signals transmitted by satellites 62, so that the locations determined by GPS receivers 12 are accurate to within about one meter.

[0043] In the specific scenario illustrated in FIG. 2, participant 42 a fires simulated weapon 44 at participant 42 b. A laser beam 48 from simulated weapon 44 hits target sensor 46. Both the firing of simulated weapon 44 and the sensing by target sensor 46 of the impact thereon of laser beam 48 are simulated combat events. Control unit 28 of tracking device 10 a formulates a message that embodies the event of the firing of simulated weapon 44. This message includes the geographical coordinates of participant 42 a and a time stamp, both obtained from GPS receiver 12 of tracking device 10 a. Control unit 28 of tracking device 10 a stores this message in memory 34 of tracking device 10 a and also transmits this message to control center 50. Similarly, control unit 28 of tracking device 10 b formulates a message that embodies the event of the sensing by target sensor 46 of the impact thereon of laser beam 48. This message includes the geographical coordinates of participant 42 b and a time stamp, both obtained from GPS receiver 12 of tracking device 10 b. Control unit 28 of tracking device 10 b stores this message in memory 34 of tracking device 10 b and also transmits this message to control center 50.

[0044] In response to the messages received from participants 42, control center 50 sends messages of its own to participants 42. Control center 50 sends a message to participant 42 b, via tracking device 10 b, that, because of the direct hit of laser beam 48 on target sensor 46, participant 42 b is “dead” and must stop participating. Meanwhile, participant 42 a has fired simulated weapon 44 a number of times equal to the number of rounds of ammunition that participant 42 a would carry into combat. Therefore, control center 50 sends a message, to tracking device 10 a and to participant 42 a, that disables simulated weapon 44 and that informs participant 42 a that participant 42 a is “out of ammunition”. These two messages from control center 50 also are recorded in memories 34 of their respective tracking devices 10.

[0045] Periodically, tracking devices 10 a and 10 b send tracking messages to control center 50. A tracking message includes geographical coordinates and a timestamp from GPS receiver 12, and also a value of a physiological parameter from sensor 30. If the geographical coordinates of a participant 42 indicates that that participant 42 is in an illegal location, control center 50 sends that participant 42 a message, via speaker 31, indicating that that participant 42 has trespassed and must return to a legal location. If the received value of the physiological parameter of a participant 42 is outside a predetermined normal range, indicating that that participant is in distress, control center 50 initiates emergency action. A distress message also may be initiated by a participant 42, by pushing alarm button 32. Pushing alarm button 32 activates the transmission of a distress message from tracking device 10 to control center 50. Like the routine tracking messages, this distress message includes geographical coordinates and a timestamp from GPS receiver 12. Upon receipt of a distress message, control center 50 initiates emergency action.

[0046] In addition to including the values of the physiological parameter in the tracking messages, control unit 28 also monitors these values itself. If the values start to fall outside the predetermined normal range, control unit 28 sounds an alarm, using speaker 31, to indicate to participant 42 that participant 42 must take corrective action.

[0047] GPS receiver 12 must have a clear line of sight to at least four satellites 62 in order to obtain a location fix. In cluttered environments, GPS receiver 12 may have a clear line of sight to only three or fewer satellites 62. In such a case, control unit 28 uses one of several known methods for using signals from both satellites 62 and BTSs 60 to obtain a location fix. See for example U.S. Pat. No. 5,945,944 to Krasner, U.S. Pat. No. 5,999,124 to Sheynblatt, International Patent Application WO99/61934 to Camp, and U.S. Pat. No. 5,982,324 to Watters et al. All four of these documents are incorporated by reference for all purposes as if fully set forth herein.

[0048] While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention may be made. 

What is claimed is:
 1. A tracking device, comprising: (a) a SPS receiver; (b) a communications interface for reversibly mounting therein a communications card; (c) a combat simulation device interface; and (d) a control unit for receiving location data from said SPS receiver, for transmitting said location data via said communications interface, and for exchanging combat simulation data between said combat simulation device interface and said communications interface.
 2. The tracking device of claim 1 , wherein said communications interface is a PCMCIA interface.
 3. The tracking device of claim 1 , wherein said communications interface is a serial interface.
 4. The tracking device of claim 1 , wherein said communications card operates according to a communications protocol selected from the group consisting of CDPD, GSM, CDMA and TETRA.
 5. The tracking device of claim 1 , further comprising: (e) a transceiver, operationally connected to said communications interface.
 6. The tracking device of claim 1 , further comprising: (e) a personal sensor, said control unit being operative to receive personal status data from said personal sensor and to transmit said personal status data via said communication interface.
 7. The tracking device of claim 6 , wherein said personal sensor is selected from the group consisting of pulse rate sensors and thermometers.
 8. The tracking device of claim 1 , wherein said control unit is operative to compress data to be transmitted via said communications interface and to decompress data received via said communications interface.
 9. The tracking device of claim 1 further comprising: (e) an alarm button for activating a transmission of an alarm signal via said communications interface, said alarm signal including at least a portion of said location data.
 10. The tracking device of claim 1 , wherein said control unit includes a memory for storing at least a portion of said data.
 11. A combat simulation system comprising: (a) a control center including: (i) a control center communications interface for reversibly mounting therein a control center communications card that operates according to a communications protocol, and (ii) a control center transceiver, operationally connected to said control center communications interface; and (b) a plurality of tracking devices, each said tracking device including: (i) a combat simulation device interface, (ii) a SPS receiver, (iii) a tracking device communications interface for reversibly mounting therein a tracking device communications card that operates according to said communications protocol, (iv) a tracking device transceiver, operationally connected to said tracking device communications interface, for transmitting transmitted signals to said control center and receiving received signals from said control center via said control center transceiver, and (v) a control unit for: (A) receiving location data from said SPS receiver, (B) transmitting said location data to said control center via said tracking device transceiver and said control center transceiver, and (C) exchanging combat simulation data between said combat simulation device interface and said control center, via said tracking device transceiver and said control center transceiver, said data being transmitted and received by said transceivers as said signals.
 12. The combat simulation system of claim 11 , wherein said communications interfaces are PCMCIA interfaces.
 13. The combat simulation system of claim 11 , wherein said communications interfaces are serial interfaces.
 14. The combat simulation system of claim 11 , wherein said communications protocol is selected from the group consisting of CDPD, GSM, CDMA and TETRA.
 15. The combat simulation system of claim 11 , wherein each said tracking device further includes: (vi) a personal sensor, said control unit being operative to receive personal status data from said personal sensor and to transmit said personal data to said control center via said tracking device transceiver and said control center transceiver.
 16. The combat simulation system of claim 15 , wherein said personal sensor is selected from the group consisting of pulse rate sensors and thermometers.
 17. The combat simulation system of claim 11 , wherein said control unit of each said tracking device is operative to compress said data that are transmitted to said control center to form said transmitted signals and to decompress said received signals to form said data that are received from said control center.
 18. The combat simulation system of claim 11 , wherein each said tracking device further includes: (vi) an alarm button for activating a transmission of an alarm signal from said tracking device transceiver to said control center via said control center transceiver, said control unit and said tracker device transceiver being operative to include at least a portion of said location data in said alarm signal.
 19. The combat simulation system of claim 11 , wherein each said control unit includes a memory for storing at least a portion of said data.
 20. A tracking device, comprising: (a) a SPS receiver; (b) a communications interface for reversibly mounting therein a communication card; (c) a personal sensor; and (d) a control unit for receiving location data from said SPS unit, for receiving personal status data from said personal sensor, and for transmitting said data via said communications interface.
 21. The tracking device of claim 20 , wherein said communications interface is a PCMCIA interface.
 22. The tracking device of claim 20 , wherein said communications interface is a serial interface.
 23. The tracking device of claim 20 , wherein said communications card operates according to a communications protocol selected from the group consisting of CDPD, GSM, CDMA and TETRA.
 24. The tracking device of claim 20 , further comprising: (e) a transceiver, operationally connected to said communications interface.
 25. The tracking device of claim 20 , wherein said personal sensor is selected from the group consisting of pulse rate sensors and thermometers.
 26. The tracking device of claim 20 , wherein said control unit is operative to compress said data prior to said transmission of said data.
 27. The tracking device of claim 20 , further comprising: (e) an alarm button for activating a transmission of an alarm signal via said communications interface, said alarm signal including at least a portion of said location data.
 28. A tracking device, comprising: (a) a SPS receiver; (b) a communications interface for reversibly mounting therein a communication card; (c) an alarm button for activating a transmission of an alarm signal via said communications interface; and (d) a control unit for receiving location data from said SPS unit, for transmitting said data via said communications interface, and for including at least a portion of said location data in said alarm signal.
 29. The tracking device of claim 28 , wherein said communications interface is a PCMCIA interface.
 30. The tracking device of claim 28 , wherein said communications interface is a serial interface.
 31. The tracking device of claim 28 , wherein said communications card operates according to a communications protocol selected from the group consisting of CDPD, GSM, CDMA and TETRA.
 32. The tracking device of claim 28 , further comprising: (e) a transceiver, operationally connected to said communications interface.
 33. A personal tracking system comprising: (a) a control center including: (i) a control center communications interface for reversibly mounting therein a control center communications card that operates according to a communications protocol, and (ii) a receiver, operationally connected to said control center communications interface; and (b) a plurality of tracking devices, each said tracking device including: (i) a SPS receiver, (ii) a tracking device communications interface for reversibly mounting therein a tracking device communications card that operates according to said communications protocol, (iii) a personal sensor; (iv) a transmitter, operationally connected to said tracking device communications interface, for transmitting signals to said control center via said receiver, and (v) a control unit for: (A) receiving location data from said SPS receiver, (B) receiving personal status data from said personal sensor, and (C) transmitting said data to said control center via said transmitter and said receiver, said data being transmitted by said transmitter and received by said receiver as said signals.
 34. The personal tracking system of claim 33 , wherein said communications interfaces are PCMCIA interfaces.
 35. The personal tracking system of claim 33 , wherein said communications interfaces are serial interfaces.
 36. The personal tracking system of claim 33 , wherein said communications protocol is selected from the group consisting of CDPD, GSM, CDMA and TETRA.
 37. The personal tracking system of claim 33 , wherein said personal sensor is selected from the group consisting of pulse rate sensors and thermometers.
 38. The personal tracking system of claim 33 , wherein said control unit of each said tracking device is operative to compress said data to form said signals.
 39. The personal tracking system of claim 33 , wherein each said tracking device further includes: (vi) an alarm button for activating a transmission of an alarm signal from said transmitter to said control center via said receiver, said control unit and said transmitter being operative to include at least a portion of said location data in said alarm signal.
 40. A personal tracking system comprising: (a) a control center including: (i) a control center communications interface for reversibly mounting therein a control center communications card that operates according to a communications protocol, and (ii) a receiver, operationally connected to said control center communications interface; and (b) a plurality of tracking devices, each said tracking device including: (i) a SPS receiver, (ii) a tracking device communications interface for reversibly mounting therein a tracking device communications card that operates according to said communications protocol, (iii) a transmitter, operationally connected to said tracking device communications interface, for transmitting signals to said control center via said receiver, one of said signals being an alarm signal, (iv) an alarm button for activating a transmission of said alarm signal, and (v) a control unit for receiving location data from said SPS receiver, for transmitting said data to said control center via said transmitter and said receiver, said data being transmitted by said transmitter and received by said receiver as said signals, and for including at least a portion of said location data in said alarm signal.
 41. The personal tracking system of claim 40 , wherein said communications interfaces are PCMCIA interfaces.
 42. The personal tracking system of claim 40 , wherein said communications interfaces are serial interfaces.
 43. The personal tracking system of claim 40 , wherein said communications protocol is selected from the group consisting of CDPD, GSM, CDMA and TETRA.
 44. The personal tracking system of claim 40 , wherein said control unit of each said tracking device is operative to compress said data to form said signals.
 45. A method of simulating combat between an aggressor participant and a defender participant, comprising the steps of: (a) providing each participant with a tracking device including: (i) a SPS receiver; and (ii) a communications interface for reversibly mounting therein a communications card, both said communications cards operating according to a common communications protocol; (b) providing each participant with a combat simulation device operationally coupled to said tracking device of said each participant; (c) providing a control center for coordinating the simulated combat; (d) simulating an attack by the aggressor participant against the defender participant, using respective said combat simulation devices, said simulating including the steps of: (i) for each participant, determining a location of said each participant, using said respective SPS receiver, and (ii) for each participant, transmitting data related to said attack to said control center via said respective communications interface, said data of each said participant including said respective location.
 46. The method of claim 45 , further comprising the step of: (e) for each participant, mounting a respective said communications card in said communications interface, prior to said simulated attack.
 47. The method of claim 45 , wherein said communications protocol is selected from the group consisting of CDPD, GSM, CDMA and TETRA.
 48. The method of claim 45 , wherein said simulating further includes the step of: (iii) for at least one of said participants, including in said data a respective time of said simulated attack.
 49. The method of claim 45 , further comprising the step of: (e) for each participant: (i) periodically determining said location of said each participant, using said respective SPS receiver, (ii) transmitting said location to said control center, and (iii) if said location is an illegal location, transmitting a trespass signal to said each participant, by said control center.
 50. The method of claim 45 , wherein each said tracking device further includes: (iv) a memory and wherein said simulating further includes the step of: (iii) recording respective said data in said respective memory.
 51. A method of monitoring a location and a condition of a subject, comprising the steps of: (a) providing the subject with a tracking device including: (i) a SPS receiver, (ii) a communications interface for reversibly mounting therein a communications card, and (iii) a condition sensor for sensing a value of a physiological parameter of the subject; (b) providing a control center; (c) periodically sensing said value, by said tracking device, using said condition sensor; and (d) if said value is outside a predetermined range: (i) determining the location of the subject, by said tracking device, using said SPS receiver, and (ii) transmitting, to said control center, by said tracking device, via said communications interface, an indication of the location and of said value.
 52. The method of claim 51 , wherein said communications card operates according to a protocol selected from the group consisting of CDPD, GSM, CDMA and TETRA.
 53. The method of claim 51 , further comprising the step of: (e) mounting said communications card in said communications interface, prior to said providing of the subject with said tracking device.
 54. A method of monitoring a location of a subject, comprising the steps of: (a) providing the subject with a tracking device including: (i) a SPS receiver, and (ii) a communications interface for reversibly mounting therein a communications card; (b) providing a control center; and (c) activating said tracking device, by the subject, to: (i) determine the location of the subject, using said SPS receiver, and (ii) transmit the location to the control center, via said communications interface.
 55. The method of claim 54 , wherein said communications card operates according to a protocol selected from the group consisting of CDPD, GSM, CDMA and TETRA.
 56. The method of claim 54 , further comprising the step of: (e) mounting said communications card in said communications interface, prior to said providing of the subject with said tracking device. 